We have previously shown that, similar to tumour-associated TEMs (Pucci et al, 2009), Phd2+/− macrophages do not upregulate either Vegf or inflammatory genes, but instead express increased levels of Tie2, Nrp1, Cxcr4, Pdgfb and Sdf1, which together may enhance their proarteriogenic capacity (Takeda et al, 2011). The gene discussed is EGLN1; the disease is neoplasm.